The chronic, inflammatory reaction in periodontal disease is induced by bacterial plaque and appears to be dependent on the immune response of the host; the interactions of antibodies, complement, neutrophils, lymphocytes, monocytes and lymphokine production. Our recent findings indicate that children and young adults with juvenile diabetes may have a very high incidence of severe periodontal disease with alveolar bone loss. Patients with diabetes have also been reported to have defective functions of phagocytes, including impairment of neutrophil chemotaxis. Defective phagocyte function has repeatedly been associated with severe periodontal disease in both humans and some animal models. The objectives of this research proposal are: 1) To establish the prevalence and severity of periodontal disease in juvenile diabetes, 2) To study the role of immune response in pathogenesis of periodontal disease in juvenile diabetes, 3) To devise a general scheme for the prevention and treatment of periodontal disease in juvenile diabetics. To accomplish these objectives we will examine the dental status of appxoimately 200 children and young adults with juvenile diabetes at the Children's Hospital Clinic at regular intervals. We will attempt to isolate the pathogenic micro-organism in patients with severe periodontal disease. We will study the alteration of humoral immunity, cellular immunity, complement activation and phagocytic activity in juvenile diabetes as they may contribute to the development of periodontitis. Finally, we will attempt to devise a general scheme for the prevention and treatment of periodontal disease in juvenile diabetes. These studies should lead to our better understanding of host defense mechanisms against oral microbial pathogens and help us to develop a more effective means of treatment and prevention of periodontal disease, and its complications in juvenile diabetes.